Wisconsin Mac & Cheese is Noodles' best seller. This company, which has 461 locations nationwide, serves up 10 million orders of mac and cheese annually with one in five customers opting for mac, Boennighausen said. This year, Noodles is on pace to dish out 2 million pounds of cheese sauce.

Wisconsin holds a special place in the company's history and the company holds a special place in Wisconsinites' appetites.

Founder Aaron Kennedy earned his MBA in 1989 from UW-Madison. Kennedy went on to open the first Noodles & Company in 1995 in Denver, Colorado. The second Noodles & Company restaurant opened in 1996 on State Street in Madison. Since the original Denver restaurant moved, the State Street spot owns the title as the company's longest consecutively-serving restaurant.

Wisconsin is now home to about 10% of Noodles restaurants in the United States (only Illinois and Colorado have more) but it drives 17% of the chain's mac and cheese sales.

Still, a few years ago the company felt its cheese sauce needed an upgrade, says Boennighausen, a 15-year veteran at Noodles.

"The quality of the cheese sauce had slipped and didn’t meet our standards," he said.

Culinary teams and cheesemakers united to improve what Sartori master cheesemaker Pam Hodgson called one of the restaurant's "flagship" dishes.

"They realized they had to innovate to stay ahead of the competition," Hodgson said.

A few round trip flights between Wisconsin and Colorado were taken. Test kitchens were fired up. Emails, calls and other telecommunications were exchanged. And finally, testing was conducted with panels and in a few select markets.

BBQ Pork Mac, part of Noodles & Company lineup of macs, features sauce made with cheese from Wisconsin cheesemaker Sartori.(Photo: Danny Damiani/USA TODAY NETWORK-)

The whole process took about a year, says Hodgson, which is typical for a project of this scope.

Boennighausen and Hodgson won't reveal the exact blend of cheeses in the new recipe, but say the most notable addition is aged cheddar.

The new sauce went nationwide in October 2017 at the same time Noodles added popular limited-time mac and cheese dishes to its lineup of "World Famous Macs." Think BBQ Pork Mac and Buffalo Chicken Mac.

Zoodles, noodles made from zucchini, appeared on the restaurant's menus last May. With zoodles came the Zucchini Truffle Mac made with the aforementioned veggie noodles, cheese sauce, black truffle, roasted mushrooms, Parmesan and toasted bread crumbs.

And Sartori cheeses can be found in more than Noodles' mac and cheeses, including its Parmesan and feta. Noodles' Alfredo features one of the cheesemaker's signature cheeses: MontAmore.

"While we can’t talk about specific sales, we do feel we can specifically point to the new and improved mac and cheese as one of the turning points in the company’s trajectory the past couple years," said Boennighausen. "The Wisconsin Mac & Cheese continues to be our number one seller nationwide."

Free mac and cheese

Noodles & Company customers who are part of the rewards program or sign up by Saturday, July 13, get a free small bowl of Wisconsin Mac & Cheese on National Mac and Cheese Day, Sunday, July 14 with the purchase of an entree.